In biology and systems theory, descent with modification. The process by which the gene pool of a population gradually changes in response to environmental pressures, natural selection, and genetic mutations.
Evolution operates on populations that involve variation among individuals, traits being inheritable, and a level of fitness for individuals that is a function of the possessed traits. Evolution produces permanent change in the morphology and function of adult living organisms, so that ancestor taxa are modified into descendant taxa. Over relatively long periods of time, the distribution of inheritable traits will tend to reflect the fitness that the traits convey to the individual; thus, evolution acts as a filter that selects fitness-yielding traits over other traits. These changes take place over chronologically successive generations between chronologically successive populations within clades or species (microevolution), or involve the emergence of new clades, species and higher taxa (macroevolution). The theory of evolution through natural selection was first proposed by Old Earth hu Charles Darwin. See also artificial evolution.
- Artificial Evolution - Text by M. Alan Kazlev
Directed evolution, evolution guided by artificial selection, controlled environments, gengineering, bionano, or other such means, as opposed to evolution left to natural selection.
- Autoevolution - Text by Anders Sandberg
Evolution directed by intelligent beings instead of natural selection.
Autoevolutionist: Someone who regards autoevolution as desirable; the opposite of a biological fundamentalist.
- Clade (evolution)
- Cladogram (evolution) - Text by M. Alan Kazlev
Branching diagram that depicts divergence of the analysed taxa from their common ancestors. It shows the distribution and origins of unique shared characteristics (synapomorphies and autapomorphies), as well as their monophyly. A testable hypotheses of phylogenetic relationships.
- Coevolution - Text by M. Alan Kazlev
Two or more organisms experiencing evolution in response to one another. This may result in a biological arms race, or it could produce a symbiotic relationship.
- Convergent Evolution - Text by M. Alan Kazlev
When a trait develops independently in two or more evolutionary sequences or groups of organisms; e.g. the development of skin-flap wings in pterodactyls and bats. Mathematically, this refers to dynamic systems settling into an attractor.
- Darwinian Evolution
- Evolution (esoterics)
- Evolution (philosophy)
- Evolution (sophontology)
- Evolutionarily Stable Strategy - Text by Anders Sandberg in his Transhumanist Terminology
Strategy which remains the most optimal even when there are a small number of individuals using other strategies in the population.
- Evolutionary Algorithm - Text by M. Alan Kazlev
A computer program that simulates the processes biological evolution; a problem-solving system that use computational models of evolution as key elements of design. All alife, evolutionary ai and aioids, and self-evolving virchworlds are determined by evolutionary algorithms.
- Evolutionary Track - Text by M. Alan Kazlev
The change in location of a star on the Hertzsprung - Russell (H-R) Diagram. As a star ages and evolves, you can trace out its history on the H-R diagram.
- Evolutionary Tree - Text by M. Alan Kazlev
Phylogenetic or cladistic diagram tracing ancestry-descent, branching, cross-links of genetic/informational and morphotypic exchange, and other factors in order to provide a complete and usually multi-parameter diagram of the evolutionary history of any taxon. A beautiful collection of evolutionary trees can be seen in the great Phylogeny Orbitals of Darwinia (NuiHibbert Sector, Zoeific Biopolity).
- Lamarckian Evolution - Text by Peter Kisner
Evolution through acquired characteristics. The concept was named after the early Industrial Age Old Earth scientist and evolutionist Jean Baptiste Lamarck, who explored the idea in detail, although the fundmental idea is not original to him. He thought to explain long term evolutionary change through this mechanism; a process where characteristics acquired by the parent are passed on to the child (i.e. giraffe ancestors stretched their necks more and more, passing on their long necks to their children). It was subsequently shown (Middle Industrial to Atomic Age Old Earth) shown that the mainspring of Terragen biotic evolution was actually the result of Darwinian selection and Mendelian inheritance; even though some traits are inherited in a Lamarckian fashion through epigenetic effects and have an effect from generation to generation they do not account for speciation.
Lamarckian Evolution in the case of AIs and even some highly reactive neogen biont clades is a valid description of their modes of longer term generational change.
- Megaevolution - Text by M. Alan Kazlev
Dramatic evolutionary change, for example the appearance of new phyla or even kingdoms of organisms. An example is the Cambrian explosion on old Earth. Natural megaevolution only occurs infrequently (often no more than once or several times on a Garden World), but gengineers and biosculptors frequently create radical new organisms by biotech and bionano means.
- Microevolution - Text by M. Alan Kazlev
Morphologic change through natural selection within a species, leading eventually to the evolution of a new species. Most common through genetic drift of small populations on individual habitats. Wild bionano can also encourage microevolution, even among large population pools. Microevolution eventually results in macroevolution.
- Phyle - Text by M. Alan Kazlev
A major category of sentient beings, as defined by one or a few basic but distinctive qualities, not necessarily connected by ancestry - e.g. biont, relativist, cycler, vec, bioborg, etc.
- Phylogeny - Text by M. Alan Kazlev
The science and art of tracing family trees of ancestry and descent, whether regarding the evolution of species over millions of years, or of terragen clades or genetic houses over thousands of years.
- Software Based Evolution - Text by M. Alan Kazlev
Software simulation of the evolutionary process; the fundamental principle of alife. Beginning in the early information period, software-based evolution enabled "creatures" which are software simulations of biological organisms, in which each cell has its own DNA-like genetic code. Digital organisms and subsophont alifes compete with one another for the limited simulated space and energy resources of their simulated environment. Although many other variations have since been used, darwinian selection remains a potent factor in the evolution and cladization of alife.